let jspang="技术胖";
let blog="大家好,我是你们的老朋友(" + jspang + ")欢迎大家,这是拼接字符串的课程";
let blog2=`大家好,我是你们的老朋友<br/>(
    <b>  ${jspang}  </b>
    )欢迎大家,
    这是拼接字符串的课程 <br>`;

document.write(blog);
document.write("<br>");
document.write(blog2);

let a=1;
let b=2;
let result = `${a+b}`;

document.write(result);

//字符串查找
document.write("<br>");
document.write(blog.indexOf("技术胖"));
document.write("<br>");
document.write(blog.includes("技术胖"));
document.write("<br>");
document.write(blog.startsWith("大家好"));
document.write("<br>");
document.write(blog.endsWith("大家好"));
document.write("<br>");
document.write(blog.repeat(10));